The overarching goal of the current SBIR Phase II project is to further develop and commercialize the Sniff Magnitude Test (SMT) so it can be used to better evaluate olfactory loss in humans. The SMT is based on the reflex-like reduction in sniffing that is observed when an odor stimulus is encountered. This response appears to be part of a fast-acting olfactomotor circuit, and therefore does not rely on higher-order cognitive abilities required to complete odor identification tests. Owing to its simplicity, the SMT provides a rapid, reliable and valid test of olfactory function that can be used for the evaluation of patients of diverse ages, cultural backgrounds, linguistic ability and cognitive status. The SMT has potential for use with patients concerned with smell loss, and may be of value in the diagnosis of several neurodegenerative disorders including Alzheimer's and Parkinson's disease. A strategic partnership has been arranged for the manufacturing and marketing of the SMT but FDA approval must be obtained before this effort can move forward. The proposed projects are clinical trials that would involve testing several patient populations known to suffer from olfactory deficits with the goal of demonstrating that the SMT can be used safely and effectively in these groups. These data would then be used as the foundation for a 510(k) application for FDA approval of the SMT. This application is being made under the newly revised NIH policy that provides for SBIR Phase II extension funding when FDA approval is a necessary step toward commercialization.